PROPRANOLOL-INDUCED SEIZURES IN MICE - THE ROLE OF NORADRENALINE

The effects of some noradrenergic agents, phenobarbitone, diazepam and phenytoin on seizures produced by propranolol were investigated in mi ce. Isoprenaline and DL-threo-3,4-dihydroxyphenylserine (DOPS) effecti vely antagonized the seizures elicited by propranolol. Pargyline and i mipramine significantly attenuated propranolol-induced seizures and al so significantly potentiated the protecting effect of DOPS against the seizures. alpha-Methyl-p-tyrosine disulfiram and reserpine significan tly potentiated propranolol-elicited seizures. However, DOPS significa ntly antagonized the seizure-potentiating effects of alpha-methyl-p-ty rosine, disulfiram and reserpine. Phenylephrine, clonidine, prazosin, idazoxan, phenobarbitone, diazepam and phenytoin did not significantly alter propranolol-induced seizures. These results suggest that propra nolol-induced seizures in mice may involve a noradrenergic mechanism m ediated via central beta-adrenoceptors.